Water Quality in Channel Catfish Production Ponds

Lloyd

1984

Hydrobiologia

Seasonal changes in the quantity and quality of phytoplankton were studied in six channel catfish culture ponds . Chlorophyll a concentrations were generally highest in the summer (averaging >200 µg 1-1 ) but the highest individual chlorophyll a value recorded (910 jig 1 -1 ) occurred in the winter during a bloom of Dictyosphaerium pulchellum. On the average, green algae (Chlorophyta) and euglenoids (Euglenophyta) represented relatively constant proportions of the phytoplankton community seasonally (about 35 and 10%, respectively) . In the summer and fall, blue-green algae (Cyanophyta) became abundant . Diatoms were relatively abundant at all times and constituted the majority of the community in the winter and spring .

Section: Discussionsupporting

confidence: 56%

Section: Introductionmentioning

confidence: 99%

Phytoplankton communities in channel catfish ponds

Lloyd

1984

Hydrobiologia

“…The taxonomic composition of phytoplankton communities varied greatly among ponds on a given date and among dates for each pond; nevertheless, the phytoplankton assemblages found in the present study are qualitatively similar to previous descriptions of communities from fish ponds in east Alabama (Boyd and Scarsbrook 1974;Boyd et al 1979) and in the Mississippi Yazoo Basin Tucker 1985). The flora at both locations were typical of nutrient-enriched, warmwater fish culture ponds: communities had relatively high standing crops (as evidenced by chlorophyll a concentrations, Fig.…”

Section: Phytoplankton Communitiesmentioning

confidence: 99%

Environmental Conditions and Channel Catfish Ictalurus punctatus Production under Similar Pond Management Regimes in Alabama and Mississippi

Hariyadi

J World Aquaculture Soc

Steeby

et al. 1994

Self Cite

This study was conducted to compare water quality and channel catfish production in earthen ponds located in two dissimilar physiographic regions of the southeastern United States and supplied with water of disparate quality. Ponds at Auburn, Alabama are on acidic Piedmont soils and filled with poorly mineralized runoff water; ponds at Stoneville, Mississippi are on slightly alkaline alluvial clays and filled with groundwater of high total alkalinity and hardness. Channel catfish were stocked at 8,750 fish/ha, fed daily, and provided nightly aeration in 0.04‐ha ponds at both sites. Ponds were managed as similarly as possible. Minimum daily water temperatures and pH were higher at Stoneville than at Auburn, and there were greater concentrations of suspended clay turbidity, dissolved inorganic phosphorus, total ammonia‐nitrogen, and nitrite‐nitrogen at Auburn than at Stoneville. The taxonomic composition of the phytoplankton community was broadly different between the two sites. Taste tests revealed off‐flavor in fish at both sites, but there were no significant differences (P > 0.05) in flavor scores between sites. The quality of flavor was somewhat different between sites, and these differences in quality were thought to result from observed differences in the taxonomic composition of phytoplankton communities. All differences in water quality seemed to be directly or indirectly related to the dissimilarity in the quality of the water supply and soils at the two locations. Although some water quality variables differed between sites and changed over time at both sites, environmental conditions never deteriorated enough at either site to cause serious stress or mortality in fish. There were no significant differences (P > 0.05) in average net fish production, survival, weight of individual fish at harvest, or feed conversion ratios. Average net fish production and feed conversion ratios, respectively, were 4,905 kg/ha and 1.27 at Auburn and 5,286 kg/ha and 1.27 at Stoneville. The results of this study demonstrate the need for site‐specific investigations when conducting certain types of aquaculture research.

“…Abundance of cyanobacteria was higher at that time than for other major groups in both treatments. Cyanobacteria‐dominated phytoplankton communities are common in catfish ponds in late summer and autumn because of high feeding rates and warm water temperatures (Boyd et al ; Tucker and Lloyd ; Schrader and Dennis ). Physiological adaptations of common bloom‐forming cyanobacteria allow them to compete effectively for light in warm, nutrient‐rich environments where dense phytoplankton blooms restrict light penetration to shallow depths (Paerl and Tucker ).…”

Section: Resultsmentioning

confidence: 99%

Water Quality and Plankton Communities in Hybrid Catfish (♀ Channel Catfish, Ictalurus punctatus × ♂ Blue Catfish, Ictalurus furcatus) Ponds After Partial Fish Harvest

J World Aquaculture Soc

Mischke

Brown

et al. 2016

Twelve 0.4‐ha ponds were stocked with 10,000 hybrid catfish fingerlings in March 2015. Six ponds were partially harvested in August to remove fish larger than ∼0.57 kg. All remaining fish were removed in October and November. Partial harvest of faster‐growing fish removed ∼26% of the fish initially stocked; feeding rate (and therefore external nutrient loading) was reduced by about the same amount. However, reduced nutrient loading after partial fish harvest had no meaningful effects on water quality, phytoplankton biomass, phytoplankton and zooplankton community structure, or supplemental aeration. Lack of ecosystem change was caused by persistent internal recycling of nutrients added to the system before partial harvest and continued high (albeit reduced) external nutrient loading after partial harvest. Decisions to employ partial fish harvest to manage single‐cropped hybrid catfish ponds should be based on economic considerations and risk reduction rather than the expectation that fish biomass reduction will improve water quality.